Killay South (Welsh: Cilâ - De) was an electoral ward in the City and County of Swansea, Wales. The ward was mainly rural and consisted of some or all of the following areas: Dunvant, Ilston, Killay, Sketty and Upper Killay in the parliamentary constituency of Swansea West.

It was bounded by the wards of Dunvant and Killay North to the north; Sketty to the east; Mayals to the south; and Fairwood to the west.

results for the election held on 4th May 2017:

Killay South 2017

Party		Candidate	Votes	%	±%
	Liberal Democrats	Jeff Jones	327	36
	Conservative	Martin Edward Quale	305	34
	Labour	Greg James	272	30
Turnout			904	49
	Liberal Democrats hold		Swing

Results for the election held on 3rd May 2012:

Killay South 2012

Party		Candidate	Votes	%	±%
	Liberal Democrats	Jeff Jones	429	49
	Labour	Peter Kenneth Jones	327	38
	Conservative	Graham Richard Coombs	111	13
Turnout			867	44
	Liberal Democrats hold		Swing

Results for the election held on 1st May 2008:

Killay South 2008

Party		Candidate	Votes	%	±%
	Liberal Democrats	Jeffrey William Jones	463
	Conservative	Martyn Ford	247
	Labour	Micheal Edward Harper	168
	Green	Peter Kenneth Jones	119
Turnout				50.53
	Liberal Democrats hold		Swing

Results for the election held on 10th June 2004:

Killay South 2004

Party		Candidate	Votes	%	±%
	Liberal Democrats	Gerald Glyn Clement	798	83
	Conservative	James Barrington Green Harding	165	17
Turnout			963
	Liberal Democrats hold		Swing

Results for the election held on 6th May 1999:

Killay South 1999

Party		Candidate	Votes	%	±%
	Liberal Democrats	Gerald Glyn Clement	790	70
	Labour	Jeffrey William Walton	203	18
	Conservative	Sarah Jane Cadogan	131	12
Turnout			1,124
	Liberal Democrats hold		Swing

Results for the election held in 1995:

Killay South 1995

Party		Candidate	Votes	%	±%
	Liberal Democrats	Gerald Glyn Clement	548	51.3
	Labour	R. Johnston	301	28.2
	Conservative	P. Williams	220	20.6
Turnout				46.5
	Liberal Democrats win (new seat)

51°37′06″N 4°01′25″W / 51.61836°N 4.02360°W / 51.61836; -4.02360